Heating model of polluted and wetted insulators

As the existing heating models of insulators could not solve the problem of the presence of dry band or dry band arc on the insulator surface, a heating analytical method of polluted and wetted insulators is proposed on the assumption that water evaporation mainly depends on heat generation on the insulator surface. By introducing contamination layer surface resistivity, humid intensity and arc model, the judging condition of the generation of dry band or dry band arc and the heating model for each running state are developed and solved by numerical analysis method. The simulation results reveal the thermal distribution on the insulator surface and the impact of the presence of dry band or dry band arc on leakage current and heating. Infrared thermal imaging experiment results of polluted and wetted insulators indicate that the proposed model is reasonable and valuable for establishment of pollution model in theory.